But… In this study, 122 older adults recorded their diets. the more likely it is that one will register as statistically significant just by random sampling error. Rebecca Goldin, Professor of Mathematical Sciences at George Mason.

A good school history book, they correctly point out, does a better job of dealing with trends and causes and effects — of tying loose ends together. It also deals with a myriad of other incidents and historical personages not touched by.